Sewing-machine.



W. E. STONE.

SEWING MACHINE. I

APPLICATION FILED NOV. 29, 1901.

1,030,836, I Patented June 25, 1912.

3 BHBETS-SHEET 1.

[I G 5 S a 1 I I 27 COLUMBIA PLANcuR/um (10., WASHINGTON, D4 6.

W. E. STONE.

SEWING MACHINE.

APPLICATION IILED NOV. 29, 1901.

Patented June 25, 1912.

3 SHEETS-SHEET 2.

woeases:

COLUMBIA PLANOORAPM cm, WASHINGTON. D. c.

W. E. STONE. SEWING MACHINE.

APPLICATION FILED NOV. 29, 1901.

1,030,836, Patented June 25,1912.

3 SHEETS-SHEET 3.

ll/roeases: Ive) 7% COLUMBIA PLANOGIIAPH m WASHINGTON, D. C.

ll Tia WILLIAM EDWARD STONE, OF MARBLEHEAD, MASSACHUSETTS, ASSIGNOR T UNITED SHOE MACHINERY COMPANY, OF PATERSON, NEW JERSEY, A CORPORATION OF NEW JERSEY.

SEWING-MACHINE.

Application filed November 29, 1901.

Specification of Letters Patent.

To all whom 'it may concern."

Be it known that I, lVlLLiAM I... S'ronn, a citizen of the United States, i siding at Marblehead, in the county of E. and State of Massachusetts, have invented ertain new and useful Improvements in Sewing-Machines; and I do hereby declare the following to be a full, clear, and. exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

The present invention relates generally to shoe sewing machines and more particularly to shoe sewing machines of the wax-thread chain-stitch type of which the commercial welt and turn sewing machines are examples.

The object of my invention is to improve the construction and operation of the thread handling devices and especially the tension device and its cooperative relation with the stitch forming mechanism. I have also improved the machine in various other details hereinafter pointed out.

To the above end the present invention consists in the devices and combinations of devices hereinafter described and claimed.

In the accompanying drawings illustrating the preferred form of my invention, Figure 1 is a sectional elevation of a chainst-itch turn shoe sewing machine embodying my invention; Fig. 2 is a side elevation of a portion of the machine viewed from the opposite side from that illustrated'in Fig. 1; Fig. 3 is a side elevation of the tension device and its actuating and controlling mechanism; and Figs. 4, 5 6 and 7 are diagrams illustrating the mode of operation of the machine showing the parts in different positions which they assume during the operation of the machine.

In the illustrated embodiment of my invention I have shown it as adapted to a turn sewing machine of the Lincoln type, but it is to be noted that my invention is susceptible of embodiment in various forms of machines whether welt or turn machines employing a curved hook needle, and, in its broader aspects, whether a thread finger be employed or not, although I prefer in order to secure the best results with my invention to use it in connection with a thread finger. It is also to be noted that my invention is available for use in machines in which the stitch is set by a cam-actuated take-up as well as in machines like the machine of the drawings, in which no positively actuated devices other than the needle, looper, thread finger, and movable tension are employed to bring the stitch to its final position in the finished seam, although my invention is probably more advantageously employed in machines of the latter class.

In the embodiment of my invention illustrated in the accompanying drawings the needle 1 is the usual curved hook needle mounted in the usual needle segment 2 and actuated by the connecting rod in the usual manner from a cam-path in a camdisk mounted upon the main shaft S of the machine. The machine is provided with the usual needleguide et. The looper 5 is of the rotary type being provided with the pinion 6 actuated by the rack 7 in the usual manner. The thread finger 8 is pivoted at 9 and actuated in the usual manner by the connected rod 10 by means of the bell crank lever 11 pivoted upon a stationary part of the frame F of the machine which is actuated by a peripheral cam of one of the cam-disks mounted upon the main shaft S of the machine. The channelguide 12 is pivotally mounted upon the feed-slide and actuated in the usual manner from cams on the main shaft of the machine. The feed point 13 is also mounted upon the feed-slide and actuated in the usual manner by cams on the main shaft of the machine. The needle, needle-guide, looper, thread finger, channelguide, and feed-point may be of any suitable or preferred construction, and in and of themselves form no part of my invention.

The tension device T consists of a tension wheel 1% revolubly mounted upon a lever 15 pivoted at 16 on a fixed part of the frame of the machine. The usual friction-producing devices are provided for applying frictional resistance to the rotation of the tension wheel. The tension wheel is acted upon by a spring 17 which is connected at one end to a stationary part of the fran'ie of the machine and at the other end to an adjusting screw 18 which passes through a hole in a downwardly projected portion 19 of the lever 15, an adjusting nut 20 serving to adjust the position of the adjusting screw 18 to vary the force exerted upon the lever 15 by the spring 17. The spring 17 normally tends to move the lever 15 in the direction to keep the thread tight between the tension wheel and the stitcl1formin mechanism, and in the illustrated embodiment of the invention said spring normally tends to move the tension wheel rearwardly.

Means are provided to move the tension wheel positively in the direction to give up thread to the stitch-forming mechanism. To the above end the connecting rod 21 is pivotally connected at one end to the upper end of the lever 15, at the other end said connecting rod is connected with a lever 22 pivotally supported upon a stationary'part of the frame of the machine. The lever 22 carries at its opposite end a cam roll 23 which engages a cam-path 2f in the camdisk 25 secured to the main shaft S of the machine. The cam, the lever 22, and the connecting rod 21 constitute means for positively moving'the tension wheel in the direction of the lead of the thread, i. e. for wardly, in order to positively give up thread to the stitch-forming mechanism. The connection between the connecting rod 21 and the lever 22 consists of a pin 26 secured to the end of the lever 22 and engaging a slot 27 in the end of the connecting rod 21. lVhen the pin 26 engages the end of the slot 27 as shown in Fig. 1, the tension wheel will be positively moved forward by means of the mechanism described and at the same time the tension wheel will be capable of moving forward under the strain exerted thereon by the thread when such strain is sufficient to overcome the resistance offered to such movement by the strain of the spring 17 Suitable stops are provided to limit the movements of the lever 15, and in the machine of the drawings the stop 28 limits the backward movement of the lever 15 and the adjustable stop 29, provided with the lock nut 30, limits the forward movement of the lever 15. The cam-path 24 for actuating the tension wheel is so constructed that after the needle has advanced toward the work and begun to penetrate the same and during the time the thread finger 8 is forming a bight in the thread, the tension wheel 14 is moved positively forward a short distance to positively give up thread to the thread finger during its bight-forming movement. Thereafter the cam-path 24 acts to move the tension wheel let positively forward to give up thread to the looper during the time it is encircling the needle to lay the thread in the barb thereof. Again, the cam-path acts to positively move the tension wheel 14L forward to give up thread to the needle during the first part of the retracting stroke of the needle. It is to be observed that during the bight-forming motion of the thread finger, during the looping-motion of the looper, and during the first part of the retracting stroke of the needle, at which times thread is required by these stitch-forming devices, the tension wheel is positively moved forward in the direction to give up thread to them. After these operations of the stitch-forming mechanism have been completed, the campath 24L acts to move the lever 22 in the direction to permit the tension wheel let to move rearwardly under the influence of its spring 17 and the cam-path 2 1 is preferably so constructed that this movement of the lever 22 is such as to move the pin 26 rearwardly in the slot 27, whereby the tension wheel is left under the sole control of the spring 17, so that the tension wheel 14 is therefore acted upon by its spring 17 to exert an uninterrupted yielding strain upon the thread during the final part of the retracting stroke of the needle while the needle is setting the stitch, with the result that the strain exerted upon the thread by the needle in setting the stitch is resisted by a spring pressure so that a' stitch is set with a gradually increasing yielding strain on the thread with the attendant advantages recognized by those skilled in the art. lVhile the best results will be secured by setting the stitch against an uninterrupted yielding action of the spring 17 as above stated, sub stantial benefits can be secured by an interrupted yielding action of the spring, such for example as would occur if the projection 19 should contact with the stop 28 before the stitch setting strain was exerted on the thread, since it is important to prevent a sudden strain being brought on the thread by stitch forming mechanism.

The operation of the machine illustrated in the accompanying drawings is as follows :In Fig. 4 the needle is shown at the time during its forward movement when its point has entered the materials and after the thread finger has formed its bight of thread, and the tension wheel 1a is shown as having been moved positively forward by its cam and as having given up thread to the thread finger. The pin 26 at this time is in engagement with the end of the slot 27 so as to secure the mode of operation above stated. The needle then continues us forward movement into the position shown in Fig. 5, and the looper in that figure is shown as having completed its looping movement. During this forward movement of the needle from the position shown in Fig. 5 to the position shown in Fig. 6, the tension wheel 14' was moved by its cam farther forward to give up thread to the looper, the pin 26 remaining in engagement with the end of the slot 27. After the completion of the looping of the thread in the barb of the needle, the needle begins its retracting stroke and the parts pass from the positions shown in Fig. 5 to the positions shown in Fig. 6, in which the needle is shown as having moved rearwardly until its barb has just emerged from the materials. During this movement of the needle from the position shown in Fig. 5 to the position shown in Fig. 6, the thread finger has moved forward giving up its bight of thread to one side of the loop of thread drawn back by the needle and the tension wheel 14 has moved forward under the influence of its cam, thus giving up thread to the other side of the loop of thread drawn back by the needle, the pin 26 remaining in engagement with the end of the slot 27. During the movement of the needle from the position shown in Fig. 6 to the position shown in Fig. 7, the lever 22 is moved by its cam to move the pin 26 backward in the slot 27 and the tension wheel is now controlled solely by its spring 17 and the tension of the thread thereon, so that during the last part of the retracting stroke of the needle whileit is setting the stitch the tension wheel offers an uninterrupted yielding strain on the thread, whereby the stitch is set against a strain gradually increasing to the full tension resistance. During the first part of the forward motion of the needle from the position shown in Fig. 7 to the position shown in Fig. 4, the tension wheel 14 moves rearwardly, shortening the loop of thread standing around the shank of the needle. It is immaterial to my invention whether this shortening of the loop of thread held by the needle during its forward movement is suflicient to take all of the slack out of the loop by the time the needle reaches the position shown in Fig. 4 or not, although I prefer that the loop at this time should have little, if any, slack thread in it.

It is to be noted that my invention is not limited to the embodiment thereof illustrated in the accompanying drawings, but is susceptible of embodiment in various forms of mechanism without departure therefrom, the accompanying drawings illustrating the best form now known to me and one which is capable of effectively carrying out my invention.

It is also to be noted that if my invention was embodied in a machine in which the stitch was set by a cam-actuated take-up, the timing of the movements of the various parts would be such that the take-up would exert its stitch-setting strain upon the thread during the time the tension wheel was controlled solely by its spring.

Having thus described my invention, I claim as new and desire to secure by Letters Patent of the United States 1. A chain-stitch shoe-sewing machine, having, in combination, stitch-forming mechanism including a curved hook needle, a movable tension wheel engaging the thread leading to the side of the work opposite to that on which the needle enters, a cam for moving the tension wheel to positively give up thread to the stitch-forming mechanism, and a spring tending to move the tension wheel and arranged to yield so as to exert an uninterrupted yielding and gradually increasing strain on the thread during the setting of the stitch, substan tially as described.

7 2. A chain stitch shoe-sewing machine, having, in combination, stitch-forming mechanism including a curved hook needle, a movable tension wheel engaging the thread leading to the side of the work opposite to that on which the needle enters, a cam for moving the, tension wheel to positively give up thread to the needle and a spring tending to move the tension wheel and arranged to yield so as to exertayielding and gradually increasing strain on the thread during the setting of the stitch, substantially as described.

3. A chain-stitch shoe-sewing machine, having, in combination, stitch-forming mechanism including a curved hook needle, and a thread finger, a movable tension wheel, a cam for moving the tension wheel to positively give up thread to the thread finger, and a spring acting on the tension wheel to exert a strain on the thread during the setting of the stitch, substantially as described.

4:. A chain-stitch shoe-sewing machine, having, in combination, stitch-forming mechanism including a curved hook needle, a looper and thread finger, a movable tension wheel, a cam for moving the tension wheel to positively give up thread to the looper, and a spring acting on the tension wheel to exert a strain on the thread during the setting of the stitch, substantially as described.

5. A chain-stitch shoe-sewing machine,

having, in combination, stitchforming mechanism including a curved hook needle, a looper, and a thread finger, a movable tension wheel, a cam for moving the tension wheel to positively give up thread to the needle, looper, and thread finger, and a spring acting on the tension wheel to exert a strain on the thread during the setting of the stitch, substantially as described.

6. A chain stitch shoe-sewing machine, having, in combination, stitch forming mechanism including a curved hook needle, a movable tension wheel engaging the thread leading to the side of the work op .posite to that on which the needle enters,

having, in combination, stitch-forming mechanism including a curved hook needle, a movable tension wheel, cam-actuated means for movlng the tension wheel 1n the direction to give up, thread to the stitchforming mechanism having provision for lost-motion permitting the tension wheel to be moved by the stitch-forming mechanism under the strain of the thread exerted thereon by said mechanism, and a spring nor mally tending to move the tension wheel in the direction to keep the thread tight between the tension wheel and the stitch forming mechanism, substantially as described.

8. A chain stitch shoe-sewing machine, having, in combination, stitch forming mechanism including a curved hook needle, a pivoted lever, a tension wheel revolubly mounted on said lever, a cam lever, connec tions including a pin and slot connection between the cam lever and said first-mentioned lever for positively moving said first-mew tioned lever in one direction, and a spring' tending to move said first-mentioned lever in. the opposite direction, substantially as described.

9'. A chain-stitch shoe sewing machine having, in. combination, mechanism including a curved hook needle,

a movable tension Wheel engaging the thread his WVILLIAM EDWARD STONE.

mark

Witnesses:

FRANK TITUS, FRED W. HOMAN.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. C.

stitch forming 

